In network environment, data-flow is broken usually because of the failure of data communication equipment, such as router, switch and etc. The broken data-flow can be recovered usually by the multi-path effect of a network. Based on network protocols, the data sender can discover that there is a failure in intermediate communication equipment, and a new route is reselected to bypassing the failure equipment, as shown in FIG. 1.
Generally, the broken data-flow can be recovered by the multi-path effect of network; but in some specific situations, there are some drawbacks:
1. When communication equipment is at the edge of a network and there are no redundant routes, failure of intermediate communication equipment usually makes the communication equipment become an isolated information island.
2. In some special application, the source route has been defined and reselecting other route is not allowed for information security or other reasons.
3. Because failure detection of the equipment and route reselection are based on kinds of protocols, along with the best-effort nature of Internet, the duration from a failure of equipment to the data-flow recovery is unpredictable. For some applications, such as video and voice data transmission etc., are sensitive to the transmission time, and the transmission quality will be worse with this kind of data-flow recovery.